WASHINGTON (Reuters) - Israeli Prime Minister Benjamin Netanyahu warned U.S. President Barack Obama on Tuesday against accepting a nuclear deal with Iran that would be a "countdown to a potential nuclear nightmare" by a country that "will always be an enemy of America".

KIEV/DONETSK, Ukraine (Reuters) - Three Ukrainian servicemen were killed and nine wounded as pro-Russian rebels shelled government positions despite a ceasefire deal, the military said on Tuesday, announcing Kiev's highest casualty toll in several days.

GENEVA (Reuters) - A United Nations envoy called on Israel on Tuesday to investigate the killing of more than 1,500 Palestinian civilians, one third of them children, during the 2014 Gaza war, and to make the findings public.

WASHINGTON/PARIS (Reuters) - U.S. President Barack Obama and European leaders held a video conference on Tuesday to discuss the Ukraine crisis, and France said all agreed that a "strong reaction" would be necessary if the ceasefire reached last month in Minsk was violated.

TRIPOLI (Reuters) - Islamist militants took over Libya's Bahi oil station and the Mabrouk oilfield on Tuesday after security forces guarding the installations were forced to retreat, according to Ali Hassi, a security official in the oil protection forces.

TORONTO (Reuters) - A shopping mall in the Canadian province of Nova Scotia was closed on Tuesday and police raided a nearby house in response to what they described as a threat, just weeks after an alleged mass shooting plot in Halifax was foiled.

BOGOTA (Reuters) - Colombian authorities detained a China-flagged ship traveling to Cuba for illegally transporting around 100 tonnes of gunpowder and other materials used to make explosives and arrested the captain, the attorney general's office said.

SANAA (Reuters) - Two suicide bombers killed at least two Houthi fighters in central Yemen on Tuesday, security sources said, highlighting volatility in a country torn by rivalries between political, tribal and sectarian groups.

NEW DELHI (Reuters) - A new documentary based on the fatal gang rape of a woman in New Delhi in 2012 highlights gender inequality and sex crimes in India, with the seeming lack of remorse among those convicted of the crime shocking even the film's director.

MONTREUX, Switzerland (Reuters) - Iran on Tuesday rejected as "unacceptable" U.S. President Barack Obama's demand that it freeze sensitive nuclear activities for at least 10 years but said it would continue talks on a deal, Iran's semi-official Fars news agency reported.